Well, we finally got to the acceleration topic, which, as you know, is the change in speed over time.

Condition:
The second body was thrown vertically upward next to the first one after t with the same speed v. How long after throwing the second body and at which height h the two bodies will collide?

Solution:
Distance traveled equation
For the first body
For the second body
Accordingly, when they meet, their coordinates will coincide, i.e.,
from which
After finding time substitute it in any formula for the distance and find h
Gravitational acceleration is assumed equal to 9.8 m/s2